Hey guys,
I'm re-factoring some caching code for our web application and working
with IT to implement our new dedicated memcached servers.
We have two machines with 32Gb a piece.
The nature of our application is that multiple client communities
receive the same kind of service but with completely different data
sets and search vectors.
We want to balance the load by distributing the heavy lifting of some
search vectors to memcahce.
We can either install thin OS's on each machine and have two memcached
servers, or we can lose 4Gb off the top on each box (to the VMware
hypervisor) and create virtual memcached servers.
We run WMware ESX.
The key is that this has to be as fast as possible.
I am looking for opinions on whether or not running inside the
hypervisor will slow the speed of direct memory access by the
memcached processes living inside the virtual machines by any
significant amount relative to normal memcached response times.
The benefit we get by virtualizing is the ability to provision
memcached server pools for individual client implementations, keeping
heavier application deployments bucketed into their own pools so as
not to overwhelm and push out the smaller, less accessed
implementation's cache entries.
I am not really concerned about losing the 4Gb to the hypervisor, but
should running in a virtualized environment like this slow down our
application requests to the memcached server?
John Wheeler
Web Applications Developer
jwheeler at etherealfringe.com
336-255-8004